Electrical energy regulating means



Dec'. 16, 1 941. P. BERGER ELECTRICAL ENERGY REGULATING MEANS 2sheets-sneer 1 Filed Aug. 24, 1938 y Uv,

QU i.. fe E 4 MMM? MHP .57

Dec. 16, 1941. FI BERGER 2,265,980

ELECTRICAL ENERGY REGULATING MEANS Filed Allg. 24, 1938 2 Sheets-Sheet 24' 75 g 75 5r u' i i 5./

104A lo Patented Dec. 16, .1941

ELECTRICAL ENERGY BEGULATING MEANS Paul Berger, Chicago, Ill., ElectricManufacturing a corporation of Illinois Application August 24, 193s,serial Nc. 226,429

(ci. 17e- 124) 6 Claims.

This invention relates generally to the art of regulating the electricalenergy supplied to a. load circuit. It is directed especially toillumination, and particularly to illumination by means of gasecusdischarge tubes, and to the provision of means for regulating theintensity of illumination from such tubes.

Gaseous discharge tubes are used to provide illumination for lightingpurposes and for signs. Lighting may be accomplished by combining lightfrom separate tubes emitting dilferently colored light to produce aWhite light which is suiciently similar to natural daylight to besatisfactory for lighting purposes. vIn this art it is frequentlydesirable to be able to adjust the intensity of the light of thedifferent colors so that the resulting composite light has the propershade of white for the best lighting effectiveness. For example, thecombination of a neon tube which emits an orange-red colored light, anda closely associated mercury vapor tube having a coating of greenfluorescing salts upon its interior Walls, produces a white light. Theproportion of illumination supplied by each tube determines the color ofthe composite light, and ifthis is varied within wide limits theresultant light varies from one which is substantially green throughvarying shades in which the green becomes less predominant and the lighttakes on the character of a white light with a greenish cast, throughwhite, to White with a reddish cast and finally to a light which issubstantially orange-red. If no means are provided for regulatingthequantityV or illumination from the differently colored tubes, theymust be associated atI the outsetwith the proper proportion, which isoften attended with difliculties. Furthermore, the colored light from atube having a coating of fluorescing salts frequently undergoes a changeof intensity With use, so that proportions which may be satisfactory atthe outset may become unsatisfactory and produce a definite shade ofgreen or red after the light has been in use for a time. Under suchconditions it may be necessary to add one or more tubes to supply aden-V ciency. It is apparent that it is highly desirable assignor toThordarson Company, Chicago, Ill.,

varying the colors and the intensity. The sign may be composed of one,or of a number of colors, and it may be desired to vary the color or theintensity continuously or intermittently, or merely to adjust them tosome condition which will thereafter remain constant.

Means have been provided heretofore for adjusting the intensity ofillumination of electrical lighting sources by varying the impedance inthe electrical supply circuit. However, dlihculties attend the use ofsuch means with gaseous discharge tubes. Such tubes require a highinitial or striking voltage and a relatively low operating voltage, asis well known, and the interposition of impedance in the supply circuitfrequently causes the supply voltage to be lowered below the requiredinitial voltage, especially since the system is usually constructed soas to provide a voltage not greatly in excess of such initial voltage.The applied voltage decreases to zero value twice in each complete cycleof the alternating current supply and during these times the tubes areinoperative and open circuit conditions Aexist and the operation of thetube must be initiated twice during each cycle. Consequently flickeringof the tubes takes place, and sometimes complete extinguishment, whenthe applied voltage on open circuit is not adequate to meet the initialvoltage requirements of the tube.

It is the general object of the invention to provide an improved meansfor regulating the energy supplied to a load circuit.

It is the specinc object of the invention to provide an improved meansfor regulating the intensity of illumination of gaseous discharge tubeswhich is simple and economical, and is convenient in operation,requiring only the manipuiation of a movable member, and not requiringthe addition of tubes to supply a deciency of a color.

It is a further object of the invention to provide such a regulatingmeans which overcomes the flickering and extinguishment mentioned aboveand provides an even continuous illuminato have a means for adjustingthe color proportions in a more convenient manner,

Where surfaces and objects such as the ceilings of theatres, the spraysof fountains, and the like, are illuminated in color by` indirect light,it is frequently desired to vary the intensity and the color to obtainpleasing effects. Similarly with signs, for advertising and otherpurposes, pleastion at all intensities down to the condition in whichthe' light is substantially extinguished.

It is a still further object of the invention to provide a regulatingmeans which accomplishes 4a smooth, continuous intensity change rathering and also spectacular eects are obtained by than an irregular,step-by-step change.

To describe the invention briefly, the supply circuit for gaseousdischarge tubes usually contains a transformer of the so-calledhigh-leakage reactance type, in which there are magnetic shunts betweenthe primaryv and secondary windings, through which shunts the magneticflux leaks, or by-passes, the secondary winding. The transformer may beof the shell or core type both of which are well known, and in whichfixed stationary windings surround one leg of the magnetic core, calledthe winding leg, and the shunts are located in the spaces between thewinding leg and the other leg or legs. In accordance with thisinvention, one of the windings of the primary and secondary windings ismovable along the Winding leg into positions at varying distances fromthe other. As the distance between the windings is increased theproportion of the flux which follows the leakage path through the shuntsand the air gaps adjacent the shunts becomes greater with the resultthat the flux which follows the useful path, that is, which threads thesecondary winding, is proportionately less and the illumination of thetubes which are connected in the output of the secondary winding is-correspondingly decreased. While this is the4 effect during thatportion of the alternating current wave cycle during which the tubes areop erative, that is, the active portion of the cycle,

the variation of the distance between windings produces little or nosuch effect during the inactive portion of the cycle. At that instantthe relative reluctance of the leakage path and the useful path issubstantially the same regardless of the distance apart of the windings.As a result the initial voltage is not affected to any substantialdegree by the movement of one of the windings, and the requisite initialvoltage is always available and applied to the tubes. It has been foundin practice that the windings may be moved so far apart that theillumination is only barely visible while a steady light without anyflickering is maintained. In a modication l of the regulating means, theshunt members of the transformers, rather than one of the windings, aremovable to vary the leakage reactance.

In the drawings:

Fig. 1 is a perspective view, partly diagrammatic, of several coloredgaseous discharge tubes and a supply circuit therefor including themeans of this invention for regulating the intensity of illumination ofthe tubes;

Fig. 2 is a graphic representation of the variation of illuminationintensity provided by the invention, with particular reference to thecombination illustrated in Fig. 1;

Figs. 3 and i illustrate diagrammatically two modified forms oftheintensity regulating means of this invention;

Fig. 5 is a fragmental, sectional view of a modication of the intensityregulating means in.

which the shunt members of the supply transformer are movable to varythe leakage reactance said view being taken along line 5 5 of Fig. 6;

Fig. 6 is a sectional view, partly diagrammatic, taken along 6 6 of Fig.5; and

Figs. 7, 8 and 9 are diagrammatic plan views showing three furthermodifications of the invention.

In Fig. 1, tubes III and I I vare diierently colored gaseous dischargetubes, which may be of any desired color. For purposes ofrepresentation, tube ISI is a neon tube emitting an orange-red light,and tube II is a mercury vapor discharge tube having a coating of greenfluorescing salts,`

emitting a light which is predominantly green but also contains thevisible blue of mercury vapor. The tubes are connected separately toeachof the two secondary-windings I2 and I3 of the supply transformer I4.VThe primary winding l5 of the transformer is connected to a suitablesource of alternating current electrical energy I6 by means ofconductors II.

rl'he transformer I4 comprises a closed magnetic core composed of steellaminations. The core is of the so-called shell type, comprising anelongated central or winding leg I8 and two outer legs I3 and 2D whichare spaced from the central legk I B in the usual manner, the legs allbeing connected together at their ends by the end portions 2I and 22.The laminations are fastened together into a unitary structure by meansofiron straps Z3vwhich extend along the top and bottom surfaces of thelegs and are fastened together by means of rivets 24 and end bars 25.The latter also serve as feet for supporting the transformer and areprovided with openings 26 by means of which the transformer may befastened in posi- 20 tion upon a suitable support.

The windings all'surround the winding-leg I8 and are preferablyseparated from. the adjacent portions of the core'bymembers 2 ofelectrical insulating sheet material. The secondary winding I2 is fixedin position adjacent the end portion 2| of the core. l The inner end ofthis winding is connected to av conductor 28 which isy broughtrout andclamped between laminations of the core as shown, and the other end ofthe winding is connected to a conductor 29 which is connectedv to oneterminal of the neon tube III. The other secondary winding I3 isarranged similarly at the opposite end of the core. The inner end ofthis winding (not shown) is connected to the core in the same manner asdescribed in connectionvwith winding I2, and the other end of thewinding is connected to' one terminal of mercury tube II by conductor31. The other terminals of tubes I0 and II are connected to the core byconductors 3d and 35 respectively, and the core is connected to theground as indicated at 36. This is .a preferred method of connection,but the two terminals of each tube may be connected to the two terminalsof each winding respectively, as will be described hereinafter, if thatis desired.

Shunt members 30 of. steel laminations are positioned in the spacesbetween the central leg I8 and the outer legs I9 and A2li adjacent theside of secondary coil I2 and are separated from said core legs bymembers 32 of thin electrical tightly to maintain them in fixedposition. In the same manner shunt members 33 are arranged adjacent theother secondary Winding I3. The laminations of the shunt members arefastened together by rivets 3|.

The secondary windings are spaced apart a distance which is greater thanis usual in transformers known heretofore, and thesections of the corelegs between the shunt members 30 and 33 are relatively elongated. Theprimary winding I5 is mounted slidably upon the winding leg I3, andisreadily slidable from a position adjacent shunt members 3D to oneadjacent shunt members 33, that is, to positions at varying distancesfrom the secondary windings. The heads of rivets 2d arecountersunk so asnot to interfere With the sliding vmotion. When. the transformer isoperative in supplying energy to the load circuit there are magneticforces of repulsion between the windings, and the movable primarywinding is mounted upon winding leg portion of the winding at one sidethereof, said member having a threaded opening through which a clampingbolt 48 may pass and serve to clamp the said member Il to .the windingleg I8.

.The shunt members 30 and 33 prvide leakage paths through which themagnetic flux may bypass theportions of the core which are beyond them,these latter portions being called the secondary core portions, .thebalance, or middle portion, of the core being vcalled the primaryportion. The members of thin, insulating sheet material 32 provide airgaps between the shunt members and the core legs, and these are of athickness to regulate the magnetic reluctance of the leakage paths to begreater than the reluctance of the secondary core portions on opencircuit. Upon the closing of the secondary circuit, the current owingtherein causes an increase in the reluctance of the secondary coreportions whereby a proportion of the magnetic -flux follows the leakagepaths, this proportion becoming greater as the current in the secondarywindings becomes greater.

mary winding' I5 and secondary winding VI3 is relatively large becausemore area of legs I3, I9

and'ZIl are exposed to each other across the intervening air gaps, andthe reluctance of said leakage path is decreased while that of theuseful( path 45 is increased because of the increased distance from theprimary winding. As a resuit, a greater proportion of the iiux followsthe leakage path. 'Ihe phenomenon may also be expressed by saying thatthe coupling between the primary winding I5 and the secondary winding I3becomes weaker as the two windings are In operation, the system isenergized by clos- I ing switch 38 in the alternating current energysupply circuit. The initial flux substantially-all passes through thesecondary core portions and produces a striking voltage in the output ofthe secondary winding sufficient to initiate operation of the tubes.Immediately the impedance of the tubes decreases greatly and the currentthrough them and through the secondary winding increases. This currentopposes the iiux in the secondary core portion and increases thereluctance of such portion whereby a substantial proportion of the fluxby-passes it and follows the leakage path through the shunt members andadjacent air spaces. The path of the initial flux and of the useful fluxwhile the tubes are operative is indicated by the dotted lines and thepath of the leakage flux during operation of the tubes is indicated bydotted lines 46.

As stated heretofore the primary winding I5 is readily slidable alongthe winding leg I8 into positions at varying distances from the sftondary windings I2 and I3, this sliding movement being accomplished byhand or other suitable mechanical means. The position of the primaryWinding I5 does not have any appreciable effect upon the distribution ofthe initial or open circuit flux, and this remains substantiallyconstant under conditions whereby substantially all of it passes throughthe secondary core portions. As a result, the initial or strikingvoltage induced in each of the secondaries remains substantially thesame regardlessy of the position of the primary winding, and is alwaysadequate to initiate operation of the tubes. As a result the tubesoperate steadily under all conditions of intensity. However, during thetime that the secondary windings are operative, and closed circuitconditions obtain, theproportion of iiux which by-passes each secondarywinding is proportional to the distance between that secondary windingand the primarywinding. In Fig. 1 the primary winding is'shown as beingfarther from secondary winding I3 than from secondary winding I2.V Theleakage path 46 between primoved farther apart. The result is that theintensity of illumination of mercury vapor tube II becomes less.Conversely, the coupling between primary winding I5 and secondarywinding I2 is increased and the intensity of neon tube I0 becomesgreater. are in the positions shown in Fig. 1, the magnetic forces ofrepulsion between windings I2 and I5 are greater than those betweenwindings I3 and I5. As mentioned heretofore, there is sufficientfriction between winding I5 and winding leg I8 to prevent thisdifference from causing movement of winding (5 and the latter remainsstationary until it is moved or manipulated mechanically by hand or someother suitable means. Similarly, in the constructions which aredescribed hereinafter the movable regulating members are adapted towithstand the magnetic forces present.

In practice, the movement of primary winding I5 from a point adjacentsecondary winding I3 to a point adjacent secondary winding I2 causes asmooth decrease of illumination intensity in the mercury vapor tube I iand a smooth increase in neon tube I Il. Fig. 2 shows a graphicillustration of the manner in which the intensity of the two tubesVaries, the iine 49 representing the intensity of the neon tube and line5G the intensity of the mercury vapor tube. The dot and dash verticalline 5I represents the relative intensities of the two tubeswhen theprimary winding I5 is in the position shown in Fig. i.

The tubes it! and II are intended to be closely associated Aso that thelight given off by them is a composite, or resultant, of the light fromthe two tubes. Where two tubes, one of them emitting the orange redlight of a neon tube, and the other the green and blue light of amercury vapor tube having a coating of green fluorescing salts areassociated together in proper proportions of illumination, the resultinglight is of a white color and is satisfactory for lighting purposes. Aswas stated earlier in this description, when the primary winding I5moves beyond the region in which such a white light is obtained thelight will have a definite green, or orangered cast, depending upon thedirection in which the primary winding has been moved. The shade ofwhite, of course, varies as the proportion of orange-red varies withinthe mentioned range. It has been found that different shades aresatisfactory for different purposes. With the arrangement of thisinvention it is possible to obtain the exact shade of light desired withgreat convenience. It is also possible to restore the combination to theexact shade desired if such shade has become disturbed due to intensitychanges having occurred with use.

In the arrangement illustrated in Fig. 3 the transformer has only onestationary secondary winding 55. The closed or shell type magnetic core56 has relatively elongated legs and has a pair of shunt members 51,similar to the shunt When the windings y elements described inconnection with Fig. i, extending between the core legs and locatedadjacent the secondary winding 55. The primary Winding be is readilymovable into positions at varying distances from the secondary winding55. Gaseous vapor discharge tube be is connected in the output circuitof the secondary winding, this output circuit being somewhat differentVfrom those described in connection with Fig. i in that both terminalsoi the secondary winding are connected to the terminals oi the tube bythe conductors et. The primary winding is connected to a suitable sourceor electrical energy by means ci conductors di. In this combination, theintensity of illumination of tube bil decreases as the distance betweenthe primary andthe secondary windings increases. It is ob vious thatsuch an arrangement isuseiul for y varying the intensity of a singletube or oi a number oi tubes which may be connected in series with oneanother in the output circuit. Where it is desirable to use acombination ci more than two colors the arrangement of Fig. 3 may becombined `with that of Fig. l and the illumination intensity of all ofthe tubes may be varied as desired. Ii" it is desired to have each tubevariablev individually, a number or combinations such as is shown inFig. 3 may be used.

In Fig. l is illustrated a modification oi the invention in which theprimary Winding lsstationary and there are two secondary windings,

one of which is stationary and the other movable. The transformer has ashell type of core ill and the windings surround the winding leg in theusual manner, stationary secondary winding ii being located at one endand stationary primary winding i2 being located in adjacent spacedrelation to secondary winding il, a pair of shunt members i3 beinglocated between them, and a second pair or shunt members it beinglocated on the opposite side of primary winding 52. The secondarywinding l5 is movable along the Winding leg into positions at varyingdistances from the primary winding l2. Gaseous discharge tubes l and ilare connected in the output circuits of secondary windings li and l5,

In Figs. 5 and 6 is illustrated a transformer in A which the Variationin the leakage reactance is obtained by the movement or the shuntmembers into and out or" the air spaces between the legs of the magneticcore. The shell type core tu is of the usual construction and thesecondary windings 8l and 82 and primary winding 33 are located in fixedposition surrounding the winding leg, the primary winding being locatedbetween the secondary windings. Pairs oi shunt members 8@ and 85 arelocated between the primary winding and the secondary windings. Theshunt members are 'each slidable laterally between a pair of thinmembers of non-magnetic material 86, this material preferably beingbrass. laminations of the shunts are held together by means of rivetsB1, which also fasten these shunt members to a cross bar 83 whichextends between them. A threaded thumb screw 89 has its end portionfastened revolvably to the midportion of the-cross bar 88. A bracketmember The is mounted upon the iron straps 9i which 75 accesso that theproportion of the operating :dus which threads the secondary coreportion is increased and the voltage which is impressed upon the outputoi the secondary, and likewise the intensity oi the tube, arecorrespondingly increased. lhe` shunt members et, see Fig. 6, arefastened in a similar manner to s. cross bar b2 which is adapted to bemanipulated by a thumb screw e3 which passes through a bracket member@13. In opera1 tion, the secondary windings Si and di are conL11 nectedto gaseous discharge tubes dil and oi diderent colors. When it isdesired-to increase the intensity or tube shunt members are drawnlaterally outwardly rom'the space between the core legs. In the same waywhen it desired to increase the intensity or" tube shunt members aredrawn outwardly. When it is desired to decrease t e intensity. oi thetubes the shunt members are moved inwardly into the spaces. Thearrangement is such that the shunt members cannot be moved outwardlyfarther than a point beyond which an unsafe current is obtained in theoutput circuit. It is understood that the invention is not limited tothe mechanism including the thumb screws ior moving the shunt membersbut any suitable mechanism may be used.

In Fig. 7 is illustrated an arrangement in which both the primarywinding and 'the shunt elements are movable. The secondary windings it@and lili are mounted over the winding leg ci the core H12 in iixedposition at the ends thereof, and the primary winding M33 is mountedover the same leg and is readily slidable into position at varyingdistances from the secondary windings. The pairs or" shunt members itiland leb are arranged adjacent the secondary winding ibo and lill,respectively, and are movable laterally in the spaces between the corelegs in the same manner as is illustrated in connection with Figs. 5 and6, the cross bars it and itl and thumb screws m8 and it being used formoving the said shunt members. This construction possesses the advantagethat it is possible to supplement the intensity variation provided bymovement of the primary winding with the variation provided by movementof the shunt members.

In Fig. 8 is illustrated a transformer of the socalled core type inwhich there is only one' leg in addition to the Winding leg. rIhe coreil@ has primary winding i il mounted slidably upon the winding leg H2,and the secondary winding H3 mounted in xed position at one end oi theWinding leg. A shunt member lll is mounted adjacentl the secondarywinding i i3 in the space between theI two legs and is movable laterallyin said space in the same manner described in connection with Figs. 5andv 6, such lateral movement being imparted to it by means of thumbscrew H6.l In general, this arrangement pos' sesses properties similarto that of Fig. 7.

In Fig. 9 a transformer is illustrated which does not employ shuntmembers. For some applications it may be desirable to omit the shuntmembers. lAlthough the shunt members facilitate varying the energysupplied to the output circuit, this may be accomplished without theirpresence, the leakage path in such case being across the air spacebetween the core legs. The core 42B has primary winding I2l andSecondary winding l22 surrounding the winding leg thereof, thesewindings both being movable along the winding leg, whereby movement ofeither causes variation in the output of the secondary winding 22 byvarying the coupling between the windings.

The mechanism described above for varying the illumination intensity ofgaseous discharge tubes without impairing the steady, smooth lightemission therefrom has many useful applications. Particularly indecorative sign work they may be used to impart many pleasing colorchange effects. While the movable parts are shown as being adapted to bemoved by hand, it is obvious that they may also be moved by an electricmotor under the control of a hand switch, the motor being adapted tomove the member in either direction as desired. Mechanism may beincorporated for maving the movable members continuously to provide acontinual color change, or intermittently at desired intervals. Suchmechanism, driven by electric motors, may be readily applied to theregulating means of this invention. It may be applied to the shuntmembers as well as the movable winding.

While the invention is directed primarily to the regulation of theillumination intensity of gaseous discharge tubes, and possessesparticular advantages for, such use, as has been explained heretofore,in its broad aspects it provides means for regulating the supply ofelectrical energy to l a load circuit by regulating the transfer ofenergy from a primary winding to a. secondary winding and is of generalapplication where such regulation is desired.

I claim:

1. In combination, a discharge lamp and a transformer, said transformercomprising a substantially closed magnetic core having a relatively longwinding leg and at least one-other relatively long leg, primary andsecondary windings surrounding diiferent portions of said winding leg,and fixed magnetic shunt members located between said primary andsecondary windings and extending between said winding leg and said otherleg, at least one of said windings being movable along said winding leginto positions at varying distances from the other of said Windings,said secondary Winding being electrically connected to said dischargelamp.

2. In combination, two discharge lamps and a transformer, saidtransformer comprising a magnetic core having a winding leg, twosecondary windings surrounding different portions of said winding leg,and a primary winding surrounding said winding leg and located betweensaid secondary windings, magnetic shunt members between said primary andeach of said secondary windings, at least one of said windings beingmovable along said winding leg into Varying D- sitions, said secondarywindings being electrically connected to said discharge lampsrespectively.

3. In combination, two discharge tubes, and a transformer, saidtransformer comprising a closed magneti-c circuit core having a windingleg, two secondary windings surrounding said `winding leg and located atfixed, spaced-apart ondary windings, said secondari7 windings being,

electrically connected to said gaseous discharge tubes, respectively.

fl. In a composite lighting unit composed of two differently coloredlight sources and a source of electrical energy therefor, means forregulating the color of the light from said composite lighting unitcomprising a transformer comprising a magnetic core having a windingleg, two secondary windings .mounted in xed, spaced-apart positionssurrounding said winding leg, and a primary winding surrounding saidwinding leg and located between said secondary windings and movablealong said winding leg into varying positions between said secondarywindings, said secondary windings being electrically connected to saiddifferently colored light sources respectively, and said primary windingbeing connected to said energy source.

5. In a composite lighting unit composed of two differently coloredlight sourcesl and an electrical energy supply circuit therefor, meansin said supply circuit for regulating the color of the light from saidcomposite lighting unit comprising a transformer comprising a magneticcore having a winding leg, a primary winding and a secondary Windingmounted in fixed adjacent positions surrounding said winding leg, and avsecond secondary winding surrounding said winding leg and located onthe opposite side of said primary Winding from said first secondarywinding, magnetic shunt members between said primary winding and each ofsaid secondary windings, said second secondary winding being movablealong said winding leg into positions at varying distances from saidprimary winding, said secondary windings being electrically connected tosaid differently colored light sources respectively.

6. In combination, va discharge tube and a transformer in the input ofsaid tube, said transformer ,comprising a magnetic core having awindingI leg, primary and secondary windings Vsurrounding said windingleg, and a magnetic shunt between said primary and secondary Lwindings,said shunt providing a iiux leakage path for said transformer, one ofsaid windings being movable-along said winding leg into positions atvarying distances from` the other of said windings, and said shunt beingmovable to vary the magnetic reluctance of said flux leakage path.

PAUL BERGER.

